I like the new common/edge.h. I don't like how inconsistently we use it.
Current situation:
- enum wlr_edges and wlr_direction are designed to be used as bitset,
and are defined compatibly
- enum lab_edge is *also* designed to be used as bitset, but
incompatible with the others (LEFT/RIGHT come before UP/DOWN)
- we use an inconsistent mix of all three *AND* uint32_t (usually with
the WLR_EDGE constants rather than the LAB_EDGE constants), and
convert between them on an ad-hoc basis, sometimes implicitly
Let's clean this up:
- reorder enum lab_edge to be compatible with the two wlr enums
(check this by static_assert)
- use TOP/BOTTOM naming rather than UP/DOWN (matches wlr_edges)
- add constants for the remaining possible combinations of the 4 edges
- use lab_edge for all internal edge/direction fields, consistently
- add lab_edge_is_cardinal() as a sanity check before casting to
enum wlr_direction, and then eliminate all of direction.c/h
Instead of "enum wlr_edges direction", we now have
"enum lab_edge direction" which is not that much better. At least we
are now clear that we're overloading one enum with two meanings.
When growing or shrinking a view by snapping to an edge, a client may
ignore the requested size and instead keep its original size or
substitute a different (possibly constrained) size. In this case, the
view may not actually contact the snapped edge, and a subsequent snap
attempt will just keep re-trying (and failing) to contact the same ege.
To mitigate this, remember the last-snapped view, snapping direction and
offset of the snapping edge in snap.c; when re-attempting a snap for the
same view in the same direction, ignore the edge that was last "hit", to
allow snapping to progress beyond the problematic edge.
...to edges actually encountered by motion during interactive moves and
resizes.
In addition, ignore edge resistance and attraction for minimized views.